Sample questions
You've seen the pattern — here are a few of the actual PYQs.
CDS2017
Consider the following statements
- The chain reaction process is used in nuclear bombs to release a vast amount of energy, but in nuclear reactors, there is no chain reaction
- In a nuclear reactor, the reaction is controlled, while in nuclear bombs, the reaction is uncontrolled
- In a nuclear reactor, all operating reactors are 'critical', while there is no question of 'criticality' in case of a nuclear bomb
- Nuclear reactors do not use moderators, while nuclear bombs use them
Which of the above statements about operational principles of a nuclear reactor and a nuclear bomb is/are correct?
- A 1 and 3
- B 2 and 3 ✓
- C 4 only
- D 1 and 4
✓ Correct answer: (B)
Science & Technology › Energy & Nuclear
CDS2014
Carbon or Graphite rods are used in atomic reactors as moderators for sustained nuclear chain reaction through nuclear fission process. In this process
- A the neutrons are made fast
- B the protons are made fast
- C the neutrons are made slow ✓
- D the protons are made slow
✓ Correct answer: (C)
Science & Technology › Energy & Nuclear
Study how UPSC repeats — not just the papers
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